The Glorious Twelfth is circumscribed by rings of fire

The guns will be out on dozens of Scottish and English heather moors today, but high above the Lancashire mill town of Colne there will be none of the "Go-back! Go-back!" calls of alarmed grouse.

Instead, the start of this year's four-month shooting season will be marked by the crack and whirr of a clay pigeon machine on six square miles of hillside ruined two weeks ago by fire.

The symbolic outing by 24 shooting syndicate members highlights the latest controversy to envelop the sport, which has been embroiled in arguments about public access and the toll of weather and disease on the birds.

Better bags than last year's are expected by the end of the day, traditionally dubbed the Glorious Twelfth, but rows about roaming on moorland at the height of fire risks are unresolved. The July heatwave saw the moors at their driest since 1976 and shooting groups have called for a blanket access ban in such conditions.

"There are reports of a party of picnickers in the area an hour before the fire began," says Phil Pugh, northern area director of Basc, the British Association for Shooting and Conservation, who has a share in the moor. "It was 30C at the time, and it takes very little to start a fire when it's like that. Now the place looks like the surface of a dead planet, and it won't recover for 15 years."

The blaze is one of a series of moorland fires which have raised questions about the safety index introduced this year, which triggers the closure of heather moors to the public. Disasters included a devastating blaze on Yorkshire's Ilkley Moor, which was rated below danger level when the fire began.

"Forget about grouse - we are risking a very special habitat," said Mr Pugh, who reckons that 33 bird species, including rare hawks, will dwindle to 17 in the aftermath of the fire.

The continuing threat will not stop shooting parties today, however, with the Moorland Association confident that experience and tight controls prevent any fire risk. The group, which represents moor owners, reckons that about a quarter of potential shooting will be available this year, after "a complete wipeout" caused by damp and worm disease in 2005. "It will still be a poor year," said Amanda Anderson of the association, "but we are getting encouraging reports of restocking, including one red grouse hen hatching 15 chicks, which is fantastic."

Pressure for a blanket access ban has been opposed by walking organisations, including the Ramblers, which called the fire safety index "a sensible restriction."

The Countryside Agency, which runs the index, said many of the worst fires during the heatwave had broken out on moors already closed because of the risk. All parties are discussing a new national warning system to publicise fire risks in future heatwaves, working alongside the safety index.